Gear cutting machine



NOV. 10, 1931. E, L, FlcKETT E11-AL 1,830,753

GEAR CUTTING MACHINE Filed Feb. 23. 1929 15 sheets-sheet 1 lnvmtozy I Nov. l0, 1931., E. 1 FHCKETT ET AL GEAR CUTTING MACHINE Filed Feb. 25, 1929 15 Sheets-Sheet 2 Nov. 10, 1931. E. L. FICKETT ET AL 1,830,753

GEAR CUTTING MACHINE' Filed Feb. 23. 1929 ISI'IQehS-Sheec 5 Nov. 1G, 1931. E. L. HCKETT ET Al..

GEAR CUTTING MACHINE Filed Feb. 23. 1929 l5 Sheets-Sheet 4 E. FlcKETT ET AL.

GEAR CUTTING MACHINE Filed Feb. 2s, 1929 Q Q- Q o o viz 6 l :si:

Nov. 10, 1931.

Nov. 10, 193,1. I E. L. FlcKETT ET AL 1,830,753

GEAR CUTTING MACHINE Filed Feb. 23. 1929 15 Sheets-Sheet 6 No 1o, 1931.

E. L. FlcKETT ET AL' 1,830,753 GEAR CUTTING MACHINE 15 sheets-sheet 7 Filed Feb. 2.5. 19.29

TTORNEY Nov. 10, 1931. E. L. FlcKET ET AL' 1,830,753

GEAR CUTTING MACHINE Filed Feb. 25. 1%29 15 Sheets-Sheet 8 Nov. 10, 1931. E, 1 FlcKETT ET AL GEAR CUTTING MACHINE Filed Feb. 25. l5 Sheets-Sheet 9 mw am Il 4454. l

" Nov. 10, 1931. E. l.. FlcKETT ET AL 1,830,753

GEAR CUTTING MACHNE Filed Feb. 25. 1929 l5 Sheets-Sheet l0 Nov. 10, 1931. E. FlcKETT T AL. 1,830,753

GEAR CUTTING MACHINE Filed Feb. 25 1929 l5 Sheets-Sheet ll Nov. 1o, 1931.v

E. L. FICKETT ET AL 1,830,753

GEAR CUTTING MACHINE l5 Sheets-Sheet 12 Filed Feb. 23. 1929 flllvllllllllll INVENTORS Ernesf. Fab/cell, LimzSEGreen Nov. 10,` 1931. E. 1 FacKETT ET AL 1,830,753

GEAR CUTTING MACHINE Filed Feb. 23, 1929' l5 sheets-sheet 15 Nov. 10, 1931. E. l.. FICKETT ET Al. 1,830,753

Y E GEAR CUTTING MACHINE Filed Feb- 25. 1929 l5 Sheets-Sheet 14 Nov. 10, 1931. E. 1 FICKETT ET AL GEAR CUTTING MACHINE Filed Feb. v23. 1929 1 5 Sheetls-Sheet 15 mlfcd Patented Nov. 10, 1931 UNITED s'rfriss PATENT "OFFICE ERNEST L. EICKETT, LrNUs E. GREENE, VLADIMIR CARSHIN, lAND JAMES s. CAMPBELL, E FITCHBURG, MASSACHUSETTS, AssIGNoRs, AEY MEsNE ASSIGNMENTS, To sCURLocK GEAR CORPORATION, 0E NEW YORK, N.v Y., A `CORPORATION oE-NEW YORK ` GEAR CUTTING MACHINE a The present invention has for an object to provide an improved gear cuttingmachine.

r1`he invention has been evolvedin connection with the development of a machine for cutting spiral bevel gears and for convenience oi' disclosure this embodiment of the invention will betmore particularly described to illustrate the principles of' the invention but it will be understood that the particular description is illustrativemerely and is not intended as defining 'the limits of the invention. 1 Y

The nature and objects vof the invention will be better understood from the description of a particular machine'ior the purposes of which descrip-tion reference should be had to the accompanyingv drawings forming a part hereof and vin which- Y VFigure 1 is a frontl elevation of the machine,

Figure 2 is a plan view thereof, y Figure 3 is a side elevation of the vmachine as viewed from the right of Figs. 1 and 2,

as indicated by the arrows III in Figs. 1, 2

and 4, l s A v Figure 4 is a rear elevation of the machine as'viewed Jfrom the direction of therarrows IV in Figs. 2 and 6,

1` Figure is an enlarged detail vertical section of the work supportingspindle taken on Figure 6 is a sideelevation of*l the machine as viewed from the left of Figs. 1 and 2, as Vindicated by the arrows VI in4 Figs. 1, 2 and .Figure 7 1s an enlarged detail horizontal Y section of a change speed gearing taken on c Figure 10 isan enlargedpdetail horizontal cutter spindle driving gearing taken on the line XUL-XIII of Fig. 14, Y l

Figure 14 is an enlarged vertical detail line XIV- XIV of Fig. 3, Y

Figure 15 is an enlarged vertical detail `*section of the cutter spindle r taken on the section of the cutter spindle driving 'gearing takenon the line XV-XV of Fig. 4, y

Figure 16 is an enlarged'vertical detail section of the `work headv cam operatingcylinder taken Von the line XV-XVI of Fig. 2, Figure 17 is yan enlarged vertical detail section Vof the cutter feedV driving gearing taken on the line XVII-XVII of Figs. 2 and 6,

Figure 18 is an enlarged detail vertical section of the cutter head feed drive taken on the line XVIII-XVIII of Fig. 2,

' Figure 19 is an enlarged detail vertical section of another part of the same gearing taken on the line XIX-XIX of Fig..4,

kFigure 20 is an enlargedelevation of `the main clutch operating mechanism shown in Fig. 4,

Figure 21 is a the line XXI- XXI of Fig. 20,

section of the same taken on o Figure 22 is an enlargedxdetail plan view vlot the operative connections of the clutch operating mechanism,

Figure 23 is a diagrammatic View showing the relative positions of the cutter head teethr and blank, l n

:Figure 24'is a face lview ofthe blank mounted upon the workhead, and'V A Figure 25 is a detail'elevation of a por-,I

tion of the cutter shown in Fig. 23 as viewed towards the edge. -Y

The gear cutting machine shown in the drawings comprises a base 5, a iXed trans verse head 6, a movable cutter head 7 and a movable work head 9 slidable on ways 10 on said base. The cutter head 7 moves on the ways 12 under control of the feed screw 13 to carry the cutter 14 rearwardly during the cutting operation and again forwardly in an idle return movement. The work head 9 carries a saddle 15 which is adjustable about a verticalaxis in an larcuate guide 17 to which said saddle is clamped in adjusted position by bolts 18. The saddle is shown as positioned at an angle of 90 to the length of the machine for conveniencev of disclosure but in cutting bevel gears, it will, of course, be adjusted to an oblique angle. The work spindle 19 is rotatable in the saddle 15 and carries a work blank 2() in position to be cut by the revolving cutter 14.

The machine operates to cut the completed i gear in one continuous operation, during which` the cutter and gear are continuously rotated and, the cutter head is continuously fed all in suitably timed relation. Power is supplied to the machine through main pulley 23 which is connected to the main power shaft 24 by a main clutch 25. The mechanism forv driving the cutter head from the main power shaft 24 may comprise the train of gearingv indicated in Figs. 2, 3, 4, 6 and shown in detail in Figs. 9 and 14. This train of gearing comprises a counter shaft 2b' driven by bevel gearsl 27, 28 from the drive shaft 24 and a transverse shaft 30 driven from the 'counter shaft by speed change gears 31, 32 which may be changed as desired to vary the speed of rotation of the cutter. The transverse shaft 30 is splined and carries a worm 33 splined thereto and meshing with a worm wheel 34 on the vertical cutter spindle 35.

The mechanism for rotating'the work spindle in suitablyV timedrelation to the rota"- tion of the cutter head and'to the speed of feed of thecutter spindle comprises a change speed geartrain having gears 36, 37, 38, 39 indicated in Fig. 4 and shown in detail in Fig. 7 which gears may be changed to give any desired-ratio between the cutter drive and the work blank drive. The gears are mounted on an adjustable frame 44 which is held in adjusted position by aV clamp bolt 44. This change speed gear train is driven from the transverse shaft 30 through a vertical shaft 40 by bevel gears 41,42, the shaft 43 of the change speed gear train being driven by the bevel gears 45, 45. The ktransverse shaft 47 driven by said change speed gear train carries, as indicated in Figs; 2'. and 12, a

Y pair of bevel gears 48, 49 adapted 'to be clutched alternatively to ,thev shaft 47 by the clutch 50 to drive the shaft 51 through the bevel gear 52. This shaft 51 extends beneath the work head 9 and has a bevel gear 54 splined thereon, said gear being carried by a bearing in the work-head and meshing with a companion gear 55 on a vertical shaft 56 positioned centrally of the adjustably swiveled saddle 15. The workspindle 19 carries a worm wheel 58 in position to be driven by a worm 59 on said vertical shaft 56.

The mechanism for moving the cutter head carriage to feed the cutter across the face of the'work and after a gear is cut to return it to initial kposition is connected to the driving mechanism of the cutter spindle and of the work spindle to. operate-inltimed relation thereto. The train of gearing for operating the feed screw on the cutting stroke is connected to the transverse shaft 47 and comprises a vertical shaft at the front of the vmachine driven through the bevel gears 66,

67 anda short vertical shaftp69 driven from the'verticall shaft 65 byv the change speed gears 70 71, said short shaft carrying a worm`72 meshing with worm wheel 73 loose on the feed screw 13. Y

The above is kshown in general arrangement in Fig. 1 and in plan in Fig. 2, the detail arrangement of which is. shown in Figs. 17, 18. A clutch 75 connects the worm wheel 73 to the feed screw 13 during the cutting action.

A quick return movement of the cutter' Y head is provided through gears 77, 78, the former of which is keyed to the cutter drive splined shaft 30 and the latterjof whichis loose on the feed screw 13 as shown in detail in Fig. 18. The gear 78 is connected during the return movement of the Vcutter head by a friction clutch 79 operated by the clutch member 75. As clearly shown in Fig. 18, the clutch member 75 is operable alternatively to connect the worm wheel 73 or the gear 78 tothe feed screw and it may also rest in neutral position with both clutches open.

Control devicesv are provided whereby when a gear blank is placed on the work spindle 19 the main 'clutch 25` can be connected to start the machine, putting in operation the cutterV spindle driving mechanism, the

work spindle driving mechanism and the cutter head feed mechanism. The complete gear is cut during a single traverse of the cutter head. Preferably the control devices are arranged automatically to cause the work head to be retracted to move the' completed gear out of the path of travel of the cutter after the cutting operation.

. The Vwork head 9V is moved on its way 10 toward and from the cutter headeither man-V cylinder to draw the work head inward. t'o working position for the cuttingfoperation or to move it outward to cutter clearing position for the return movement of the cutter head. Air is admitted v to the cylinder through theV ports v88 and 89 at opposite ends of the cylinder as shown in Fig.16.

The machine is started by V- moving the hand lever y90 atthe front down to rotate the rock shaft 91 and through the arm 92 and connecting rod 93`atthe side of the machine to throw the valve control lever 95 admitting air to the forward end of the cylinder 87 This 4moves fthe cam 86 rearwardly to draw the work head 9 into gear cutting position; The slide of the cam 86 carries at its forward end two slots 97 and 98,`Fig. 2, in which engage arms 99, 100, Fig. 1, of rock shaft 101 and rock sleeve 102. The arm 99 is extended downwardlyand operatively connected to anl over-center spring 104 arranged to completethe movement of the rock shaft when it is-moved beyond dead center position in either direction. The rocking of the sleeve 102 throws in the main clutch 25 to start the machine lthroughV the vertical rod 105 and rock shaft 106 extending transversely of the machine and connected. to the clutch operating mechanism shownin detail invFigs. 20, 21. The connection between the vertical rod 105 and the rock shaft 106 comprises alost motion spring 108 by which the arm 109 of the rock shaft 106 may be yieldingly moved to clutch engaging position. The rock shaft 101 is connected to control the feed screw reversing clutch 75 and when the machine is started causes said clutch to be lmovedinto engagement with the worm wheel 7 3 to initiate the feeding of the cutter head 7. The operative connections between the rock shaft 101 andthe clutch 7 5 areshown as comprising a vertical connecting rod 110 operatingat its `upper end an arm 111 ona rocky shaft 112 which carries the clutch operating yoke 113 `of thev clutch `When the operation of cutting the gear is completed which operation requires only one Vtraverse of the cutter head, the cutter head feed mechanism vis automatically reversed to return the cutter head to initial position.

When the cutter head is completely retracted-to initial position the main clutch 25 is disconnected to stop the machine. The control mechanism for accomplishing `these operations comprises a horizontal sliding rod 115 at the top of the machineV above the cutter head and a similar sliding rod 116 beneath the cutter head. An adjustable stop 117 on the upper rod 115 is engaged by va projection 118 on the cutter head. LToward the'forward end the rod is connected to rock a rockfshaft 120 through an'ar1n121, which rockshaft in turn through an arm` 122 -moves the vertical connecting rod 123 upward to rock .the rock yvalve armor of the machine shaft 91 andstarting leverf90 upward. 'This operation' through vthe connecting `rod 93Iand lever-95 will admit air to the rearward endl lof-'the cylinder 87 lto actuate the cam v86 `and move the work head 9 away from the cutter head. This movement of the cam 86 forward will through the'arms 99 and V'100 rock the rock shaft'101 and therock sleeve 102. Asl the rock' shaft 101 lis rocked, the

clutch member 75 will be'shifted through the` connecting rod 1101a'nd arm 111 to engage the n friction clutch 79 thereby Vreversing'the feedv screw drive to return the cutter head to initial position. 102 and connections to the clutch mechanisms' will not operate to actually disconnect -the main clutch 25.

.The-slide-rod 115 is provided with an additional stop 125 which will be engaged by the projection 1118 if, because `of accident v`or otherwise, the main clutch 25l is not disconnected when it ordinarily should be.` In` such event the continued movementof the cutter head will act through the stop 125 andthe 9b operating connections to the valve lever 95 to reverse thedirection of feed of the cutter 'head'. j

A stop 127 is engaged by the cutter head and operates through suitable connections to reset mechanism `for disconnecting the main clutch 25. Toward the opposite end of this rodf116 a stop 129 is arranged tobe engagedat the end of the returnmovementof the cutter head to move the rod 116 in the opposite direction to cause actualy operation of the previously set main clutch disconnectingv mechanism. `The connections between lthe rod 116 and the clutch 25 are bestv shown in Figs. 20, 21 and 22 in detail;

to a link 132,"the movement of right in' Fig. 20 will, when the parts are suitably connected, throw out theclutchg25.

In the clutch operating mechanism shown the l no shaft 106. This arm 4 Vwith a bell crank lever`142pivoted at 1113 to the arm 138.

The bell crank lever v1112` is spring tensioned The movement of the rock shaft keyed thereto and having .1120- fin i The rod 116 is 'connected throughgear segments`180 and 131: whichv to the fils in one direction by a spring'11l5 vand its'mo'- tion in both directions relative to the arm 138 is limited by stoppins 1l16'an'd147. `Then vthe rock shaft 106 is moved in a clockwisek direction in Fig. 20 to start the machine, the

projecting piny111`of the arm'140 engages the bell crank lever or' latchy 142 andV rocks by the rock shaft 106 because thesame about zits pivot '143 causing -a .1'8- lease between the lug y148 at the lower end of the bell crank lever andan operating arm 150, and then as the bell crank lever engages the stop pin 147 further movement of the rock shaft 106 causes actual engagement of the clutch 25. 1

As long as the cutting operation continues, the main clutch Will be held in engagement;

be yieldably held in clutch engaging position by the connections to the cam 86 as previously described. However, after the Work head has been retracted by theretraction of .the cam 86 the rock shaft 106 Will no longer hold the clutch in engagement. In fact, the arm 140 Will be moved to the right in Fig. 2O leaving the clutch control leverV free to be moved to clutch disengaging position. The movement-of the rod 182 to the left in Fig. 20 will carry the arm 150 to which said rod 132 is operatively connected to the left `and behind the lug 14S of the catch or bell cram( lever 142 and the later movement of said rod 132 to the right, when the return movement of the cutter head is completed, Will move the clutch control lever to clutch disengaging position. v

Thev reversible driving4 mechanism for rolrating the Work spindle 19 is made reversible in order that right and left hand spiral bevel gears may be conveniently cut by reversing the direction of rotation of the-blank. V'lhe clutch 50 is controlled by a clutch` rod 155 arranged to be actuated by a hand lever 156 which is held in either extreme operated positioned by a spring detent. 157, Fig. 1l.

Anoil pump 158 is shown connected to be driven from a pulley 159 on the main power shaft to supply oil to the Work. The connections may be of any usual type and need not be specifically shown in the drawings.

The cutter may be of any preferred or suitable type. The preferred form of cutter is shown in Figs. 23V and 25. As there shown, the cutter comprises a head with a number of removable individual bits 160, 161 arranged in pairs, a pair of bits constituting in effect one tooth of a cutter and being arranged to operate in a corresponding space of the gear being cutone bit Working against one tOOh face and the companion bit working against the opposite tooth face. The bits are so arranged that the cutting edges 162, 163 of .the Vtwo bits arearranged in substantially the same plane in order that both faces of each spiral tooth as cut on the blank may be generated along an Archimedean Vspiral curve. This avoids the error ordinarily introduced by the thickness ofthe cutter tooth in the generation of the gear tooth.

The machine shown is used in cutting gears by a method wherein theblank and vcutter- `are continuously rotated in suitably timed relation and the it in turn will l Y.cut a complete cutterv and Work are fed nelatively'to ,move the cutter across the face ofthe blank to form a gear in one continuous cutting operation.-

.1. A gear cutting machine comprising, in combination, a movable cutter head, a rotatable cutter carried thereby, an angularly adjustable Workhead movable toward and from the path of movement of said cutter head, means for so movingy said Work head as a necessary incident to the operation of the machine, a Work supportrotatable in said Work head and means for rotating the cutter and thework support and feeding the cutter head in` timed relation to cut a complete gear during one traverse of the cutter head.

2. A. gear cuttingmachine comprising', in combination, a movable cutter head, a rot..- table cutter carried thereby, a Work head movable toward and from the path of movevment of said cutter head,.a Work support rotatable in said Work head, means for rotating the cuttcr and feeding the cutter headand means associated therewith for rotating the Work head in either direction and in suitably timed relation to cut a gear.

Y. 3. i gear cutting machinecomprising, in combination, a movable cutter head, a rotatable cutter carried thereby, a work head movable toward and from the path of movement of said cutter head,a Work support rotatable in said Work head, means for rotating the cutter and the Work support and feeding the cutter head in timed relation to gear during one traverse of the cutter head and control means operable to first move the Work head toward the path of movement of the cutter i the rotating and feeding means in operation.

4. gear cuttingmachine comprising, in

combination, a movable cutter head, a roatable cutter' carried thereby, a movable Work head, a'Worl-r support rotatable in said Work head, a cam and means controlled thereby for moving the Worlr head toward the path of movement` of the cutter, driving mechanism -for i simultaneously rotating the cutter andyvorlr. supportV and feeding the cutter head in suitably timed relation to cut a gear and means controlled by said cam for setting .in operation the driving mechansm.

A gear cutting machine comprising, in combinatiom a.- n1cv ablel cutterheacha rotatable cutter lcarried thereby, awvor-k head movable toward land from the path `of movementof saidcutter head, a work support rotatable in said Worlr head, driving means for rotating*simultaneously the cutter and Work support and feeding the cutter head to cut a gear, a cam fcrfmoving the Work head, means controlled b vmovement of the cutter head to actuate said `cam and means centrolled by movementof the cam to -reverse kthe direction .of feed of the cutter head. Y

6. A ,gearcutting machine comprising, in

combination, a movable cutter head, a flat rotatable cutter carried thereby, a work head movable toward and from the path of movement of said cutter head, a saddle adjustable angularly. on said work head, a work support substantially in the plane of said cutter rotatable in said saddle and means for simultaneously rotating said cutter and work support and feeding said cutter head in suitably timed relation to cut a gear.

, 7. A machine for cutting spiral bevel gear comprising, in combination, a base, a ycutter head movable transversely of said base, a cutter rotatable therein, a work lhead movable longitudinally of said base, a saddle adjustable angularly on said work head,.a work support rotatable in said saddle, driving means for simultaneously rotating said cutter and work support including a shaft eX- tending longitudinally of the base, and a gear splined on said shaft and carried by said work head. Y

8. A gear cutting machine, as .defined in claim 7, whereinmeans is provided for driving the work support in either direction whereby to cut right or left spiral gears.V

9. Amachine for'cutting spiral bevel gears comprising, in combination, a base, acutter head movable transversely of said base, a cutter rotatable therein, a work head movable longitudinally of said base, a saddleadjustable angularly on said work head,a work` supportV rotatabley in said saddle, driving means for simultaneously rotating said cutter and worl; support including a shaft extending longitudinally ofthe base, a gear'splined on said shaft and carried by said work head, and a shaft coaxial with the angularly adjustable saddle driven by said gear. y

10. In a machine for cutting bevel gears, in combination, a rotatableworlr supporting spindle, a cutter head movable on ways at a right angle to the normal axis of said spindle, a cutter having a plurality ofI circumferentially arranged teeth, means for moving said cutter head lalong said Ways during the gear. cutting operation and for rotating said cutter in said cutter head to bring` a pluralityy of teeth simultaneously into action on a blank carried by said spindle. v.

l1. `A gear cutting machine comprising, in combination, a slidable cutter head, a rotatable-cutter carried by said head, a work head movable toward and from the cutterhead, a saddle adjustable angularly on said` work head, a work support rotatable-in said saddle and driving means for rotating vsaid Work support, comprising' a shaft coaxial with the axis of adjustment of the saddle.

12. A gear cutting machine comprising, in combination, a cutter head, a work head movable toward and from the cutter head, a work support rotatable in said work head, and means for simultaneously rotatingsaid vcutter and said Work support including .means for reversing the direction 'of ,rotationA of the work support to cut right or left handV spiral gears.

. 13. A gear cutting machine comprising, in 'i combination, a movable cutter head, a rotatable cutter carried thereby, a work head mov- "i able toward and from the path of movement of said cutter head, a work support rotatable in said work head and means for rotating the cutter and the Work support simultaneously including adjustable change speed .gearing adapted to readily vary the relative speeds of the cutter and work support.

14. A gear cutting machine comprising, in

combination, a movable cutter head, a rotat-` able cutter carried thereby, a work head movable toward and from -the path of movement of said cutter head, a work support rotatable 1n saidfwork head and meansfor simultaneously rotating the cutter and Work support and feeding the cutter head comprising adjustable change gears for readily varying the relative rates of rotation of the cutter and work support and for varying the feed of the cutter head.

15. IA lgear cutting machine comprising,

in combination, a movable cutter head, a rotatable cutter carried thereby, a work vhead movable vtoward and from the path of movement of said cutter head, a Work supporty rotatable in said work head, driving'v means forsimultaneously rotating the cutter-and work support and feeding'the cutter head to cut a gear and control means comprising a cam connected to the Work head to" move it'toward andfrom theV cutter head, and means controlled by said cam in itspdifferent positions to start the driving means and to reverse'the direction-of feed; of the cutter head. y ,Y l

16. A `gear cutting `machine comprising,k in combinatioma movable cutter head, a rotatabley cutter carried thereby, a work head movable toward and from the path of movement of said cutter head, a work support rotatable in said work head, a main power shaft, a clutch for connecting the powershaft to a vsource of power, gearing including change gears connected to said main power shaft for rotating the cutter and work support and for feeding the cutter head and means for disconnecting saidk clutch comprising a device placed under tension by movement of the lcutter head in one direction and tripped to disconnect the clutch.y by movement of the cutter head in the opposite direction. y

y17. A machine for cutting spiral bevel gears comprising, in combination, a base having transverse and longitudinal ways, a cutlter head movable on said transverse Ways, a 

